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Talwar C, Nagar S, Negi RK. Comparative analyses of gut microbiota reveal ammonia detoxification and nitrogen assimilation in Cyprinus carpio var. specularis. Folia Microbiol (Praha) 2024:10.1007/s12223-024-01151-6. [PMID: 38367166 DOI: 10.1007/s12223-024-01151-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 02/08/2024] [Indexed: 02/19/2024]
Abstract
The complex niche of fish gut is often characterized by the associated microorganisms that have implications in fish gut-health nexus. Although efforts to distinguish the microbial communities have highlighted their disparate structure along the gut length, remarkably little information is available about their distinct structural and functional profiles in different gut compartments in different fish species. Here, we performed comparative taxonomic and predictive functional analyses of the foregut and hindgut microbiota in an omnivorous freshwater fish species, Cyprinus carpio var. specularis, commonly known as mirror carp. Our analyses showed that the hindgut microbiota could be distinguished from foregut based on the abundance of ammonia-oxidizing, denitrifying, and nitrogen-fixing commensals of families such as Rhodospirillaceae, Oxalobacteraceae, Nitrosomonadaceae, and Nitrospiraceae. Functionally, unique metabolic pathways such as degradation of lignin, 2-nitrobenzoate, vanillin, vanillate, and toluene predicted within hindgut also hinted at the ability of hindgut microbiota for assimilation of nitrogen and detoxification of ammonia. The study highlights a major role of hindgut microbiota in assimilating nitrogen, which remains to be one of the limiting nutrients within the gut of mirror carp.
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Affiliation(s)
- Chandni Talwar
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India
- Department of Pathology & Immunology, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, 770030, USA
| | - Shekhar Nagar
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India
- Department of Zoology, Deshbandhu College, Kalkaji, New Delhi, 110019, India
| | - Ram Krishan Negi
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India.
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2
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Bharti M, Nagar S, Negi RK. Riverine pollution influences the intraspecific variation in the gut microbiome of an invasive fish, Cyprinus carpio (Linn., 1758). 3 Biotech 2023; 13:320. [PMID: 37649590 PMCID: PMC10462599 DOI: 10.1007/s13205-023-03747-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 08/16/2023] [Indexed: 09/01/2023] Open
Abstract
Humans are significantly impacting riverine systems worldwide, prompting us to investigate the effects of water pollution on the gut microbiome of Cyprinus carpio (common carp). Using 16S rRNA gene sequencing, we compared the gut microbiomes of common carp from two sites along river Yamuna with different pollution levels. Water pollution significantly altered the fish gut microbiome structure and microbial composition. Proteobacteria dominated in both sampling sites, while Bacteroidota prevailed in polluted water samples, indicating sewage and fecal contamination. Less polluted samples exhibited Verrucomicrobiae and Planctomycetes, negatively correlated with pollution levels. The polluted site had higher prevalence of potentially pathogenic and heavy metal-resistant bacteria, as well as microbial communities associated with wastewater treatment systems. Functional prediction highlighted the significant role of the gut microbiome in digestion and metabolism, with active enzymes for breaking down various organic substances. Biosynthetic pathways for leucine, valine, and isoleucine were present in both sites, known to be involved fish immunity. The host maintained a stable and diverse bacterial consortium, while microbial diversity became more specialized due to human activities, adapting to anthropogenic stress and selection pressures. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-023-03747-0.
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Affiliation(s)
- Meghali Bharti
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, North Campus, Delhi, 110007 India
| | - Shekhar Nagar
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, North Campus, Delhi, 110007 India
- Department of Zoology, Deshbandhu College, Kalkaji, New Delhi, 110019 India
| | - Ram Krishan Negi
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, North Campus, Delhi, 110007 India
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3
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Nagar S, Bharti M, Negi RK. Genome-resolved metagenomics revealed metal-resistance, geochemical cycles in a Himalayan hot spring. Appl Microbiol Biotechnol 2023; 107:3273-3289. [PMID: 37052633 DOI: 10.1007/s00253-023-12503-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 03/18/2023] [Accepted: 03/25/2023] [Indexed: 04/14/2023]
Abstract
The hot spring microbiome is a complex assemblage of micro- and macro-organisms; however, the understanding and projection of enzymatic repertoire that access earth's integral ecosystem processes remains ambivalent. Here, the Khirganga hot spring characterized with white microbial mat and ions rich in sulfate, chlorine, sodium, and magnesium ions is investigated and displayed the examination of 41 high and medium qualified metagenome-assembled genomes (MAGs) belonged to at least 12 bacterial and 2 archaeal phyla which aids to drive sulfur, oxygen, iron, and nitrogen cycles with metabolic mechanisms involved in heavy metal tolerance. These MAGs possess over 1749 genes putatively involved in crucial metabolism of elements viz. nitrogen, phosphorus, and sulfur and 598 genes encoding enzymes for czc efflux system, chromium, arsenic, and copper heavy metals resistance. The MAGs also constitute 229 biosynthetic gene clusters classified abundantly as bacteriocins and terpenes. The metabolic roles possibly involved in altering linkages in nitrogen biogeochemical cycles and explored a discerned rate of carbon fixation exclusively in archaeal member Methanospirillum hungatei inhabited in microbial mat. Higher Pfam entropy scores of biogeochemical cycling in Proteobacteria members assuring their major contribution in assimilation of ammonia and sequestration of nitrate and sulfate components as electron acceptors. This study will readily improve the understanding of the composite relationship between bacterial species owning metal resistance genes (MRGs) and underline the exploration of adaptive mechanism of these MAGs in multi-metal contaminated environment. KEY POINTS: • Identification of 41 novel bacterial and archaeal species in habitats of hot spring • Genome-resolved metagenomics revealed MRGs (n = 598) against Cr, Co, Zn, Cd, As, and Cu • Highest entropies of N (0.48) and Fe (0.44) cycles were detected within the MAGs.
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Affiliation(s)
- Shekhar Nagar
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India
- Department of Zoology, Deshbandhu College, Kalkaji, New Delhi, India
| | - Meghali Bharti
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Ram Krishan Negi
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India.
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Kumar R, Nagar S, Haider S, Sood U, Ponnusamy K, Dhingra GG, Anand S, Dua A, Singh M, Kumar R, Sengar M, Singh IK, Lal R. Monkeypox virus: phylogenomics, host-pathogen interactome and mutational cascade. Microb Genom 2023; 9. [PMID: 37043267 DOI: 10.1099/mgen.0.000987] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023] Open
Abstract
While the world is still recovering from the Covid-19 pandemic, monkeypox virus (MPXV) awaits to cause another global outbreak as a challenge to all of mankind. However, the Covid-19 pandemic has taught us a lesson to speed up the pace of viral genomic research for the implementation of preventive and treatment strategies. One of the important aspects of MPXV that needs immediate insight is its evolutionary lineage based on genomic studies. Utilizing high-quality isolates from the GISAID (Global Initiative on Sharing All Influenza Data) database, primarily sourced from Europe and North America, we employed a SNP-based whole-genome phylogeny method and identified four major clusters among 628 MPXV isolates. Our findings indicate a distinct evolutionary lineage for the first MPXV isolate, and a complex epidemiology and evolution of MPXV strains across various countries. Further analysis of the host-pathogen interaction network revealed key viral proteins, such as E3, SPI-2, K7 and CrmB, that play a significant role in regulating the network and inhibiting the host's cellular innate immune system. Our structural analysis of proteins E3 and CrmB revealed potential disruption of stability due to certain mutations. While this study identified a large number of mutations within the new outbreak clade, it also reflected that we need to move fast with the genomic analysis of newly detected strains from around the world to develop better prevention and treatment methods.
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Affiliation(s)
- Roshan Kumar
- Post-Graduate Department of Zoology, Magadh University, Bodh Gaya, Bihar 824234, India
| | - Shekhar Nagar
- Department of Zoology, Deshbandhu College, University of Delhi, New Delhi, Delhi 110019, India
| | - Shazia Haider
- Department of Biotechnology, Jaypee Institute of Information and Technology, Uttar Pradesh, Noida 201309, India
| | - Utkarsh Sood
- Department of Zoology, Kirori Mal College, University of Delhi, Delhi 110007, India
| | - Kalaiarasan Ponnusamy
- Biotechnology and Viral Hepatitis Division, National Centre for Disease Control, New Delhi 110054, India
| | - Gauri Garg Dhingra
- Department of Zoology, Kirori Mal College, University of Delhi, Delhi 110007, India
| | - Shailly Anand
- Deen Dayal Upadhyaya College, University of Delhi, New Delhi 110078, India
| | - Ankita Dua
- Shivaji College, University of Delhi, New Delhi 110027, India
| | - Mona Singh
- Department of Zoology, Deshbandhu College, University of Delhi, New Delhi, Delhi 110019, India
| | - Roushan Kumar
- Post-Graduate Department of Zoology, Magadh University, Bodh Gaya, Bihar 824234, India
| | - Manisha Sengar
- Department of Zoology, Deshbandhu College, University of Delhi, New Delhi, Delhi 110019, India
| | - Indrakant Kumar Singh
- Department of Zoology, Deshbandhu College, University of Delhi, New Delhi, Delhi 110019, India
- Institute of Eminence, Delhi School of Public Health, University of Delhi, Delhi 110007, India
| | - Rup Lal
- Phixgen Pvt. Ltd., Sector 55, Noida, Uttar Pradesh, India
- Acharya Narendra Dev College, University of Delhi, Govindpuri, Kalkaji, New Delhi 110019, India
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Lin S, Kahangire D, Nagar S, Ahn MJ, Affi R, Agulnik J, Shih JY, Hochmair M, Tufman A, Debieuvre D, Chow J, Jimenez M, Davis K, Sandelin M, Veluswamy R. 91P Treatment (tx) patterns and outcomes in resectable early-stage non-small cell lung cancer (NSCLC): A global real-world (rw) study. J Thorac Oncol 2023. [DOI: 10.1016/s1556-0864(23)00346-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
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Bharti M, Khurana H, Sharma M, Choksket S, Nagar S, Yadav S, Modeel S, Korpole S, Negi RK. Taxonomic and genomic characterization of Sporosarcina cyprini sp. nov., moderately tolerant of Cr +6 and Cd +2 isolated from the gut of invasive fish Cyprinus carpio var. communis (Linn., 1758). Antonie Van Leeuwenhoek 2023; 116:193-206. [PMID: 36400900 DOI: 10.1007/s10482-022-01794-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 11/02/2022] [Indexed: 11/19/2022]
Abstract
A Gram-stain-positive, motile, and rod-shaped bacterium, designated as strain MB25T, was isolated from the gut of Cyprinus carpio from the highly polluted river Yamuna, India. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain MB25T belonged to the genus Sporosarcina, sharing the highest sequence similarity with S. luteola Y1T (98.98%) and S. koreensis S-K12T (98.91%). Digital DNA-DNA hybridization and average nucleotide identity values of strain MB25T with strain Y1T and S-K12T were 18.9, 77.69, and 18.2, 76.80 respectively. Genome analysis of strain MB25T revealed its biotechnological properties such as tolerance to potent heavy metals, genes for the production of carbohydrate-active enzymes, antimicrobial compounds, and also degradation of aromatic compounds. The G + C content of strain MB25T genome was 45%. Growth observed at 10-40 °C (optimum, 28-30 °C), pH 6.0-8.5 (optimum pH 7.5-8.0); NaCl concentrations up to 6.0% (w/v). The dominant respiratory quinone was MK-7, cell wall peptidoglycan is of the A-4 type containing amino acids Lys-Glu and the major fatty acids are anteiso-C11:0 and iso-C15: 0. The major polar lipids of strain MB25T are diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. On the basis of phenotypic, chemotaxonomic, phylogenetic, and phylogenomic data, strain MB25T represents a novel species of the genus Sporosarcina, for which the name Sporosarcina cyprini sp. nov. is proposed. The type strain is MB25T (= MCC 4366 T = JCM 34521 T = CCM 9113 T).
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Affiliation(s)
- Meghali Bharti
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, New Delhi, 110007, India
| | - Himani Khurana
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, New Delhi, 110007, India
| | - Monika Sharma
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, New Delhi, 110007, India
| | - Stanzin Choksket
- CSIR-Institute of Microbial Technology, Chandigarh, 160036, India
| | - Shekhar Nagar
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, New Delhi, 110007, India.,Deshbandhu College, University of Delhi, Delhi, 110019, India
| | - Sheetal Yadav
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, New Delhi, 110007, India
| | - Sonakshi Modeel
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, New Delhi, 110007, India
| | - Suresh Korpole
- CSIR-Institute of Microbial Technology, Chandigarh, 160036, India
| | - Ram Krishan Negi
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, New Delhi, 110007, India.
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Shih JY, Lin S, Nagar S, Jimenez M, Davis K, Kahangire D, Servidio L, Ho L, Veluswamy R. 302P Treatment patterns in resectable early-stage NSCLC in Taiwan: Subgroup analysis of a global real-world study. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.10.330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
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Bharti M, Nagar S, Khurana H, Negi RK. Metagenomic insights to understand the role of polluted river Yamuna in shaping the gut microbial communities of two invasive fish species. Arch Microbiol 2022; 204:509. [PMID: 35859219 DOI: 10.1007/s00203-022-03127-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 07/05/2022] [Accepted: 07/06/2022] [Indexed: 11/26/2022]
Abstract
The gastrointestinal microbial community plays a crucial role in host health, immunity, protection, development and provides nutrients to the host. The rising human-induced pollution and heavy metal contamination in all aquatic systems globally has led us to explore the gut microbial diversity of two exotic invasive fish Cyprinus carpio (Linnaeus, 1858) and Oreochromis niloticus (Linnaeus,1857) from river Yamuna, India. These fishes are aquatic bioindicators with high demographic resilience. Exploring these associations would pave the way for addressing problems that inhabitant fishes are facing due to the increasing pollution load in the River Yamuna. Based on 16S rRNA gene amplicon sequencing, our results deliver comparative information on the gut microbiome of these fishes and highlight connotations between the microbiome of gut and water samples. The gut of C. carpio and O. niloticus was dominated by phyla Proteobacteria whereas Bacteroidetes dominated the water sample. Microbial communities showed predicted roles such as pathogenicity (Escherichia-Shigella, Aeromonas veronii, Vibrio cholerae, Streptococcus iniae, Flavobacterium columnare, Klebsiella pneumoniae, Mycobacterium sp.), probiotic applications (Bacillus velezensis, Lactobacillus plantarum, Enterococcus faecalis, Bifidobacterium longum, Lactococcus lactis, Leuconostoc falkenbergense) and involvement in sewage and organic matter decomposition (Nitrosomonas sp., Methanosaeta harundinacea, Dechloromonas agitata, Thauera humireducens, Zoogloea ramigera). Heavy metal degrading members (Leucobacter chromiireducens, Pseudomonas fluorescens, P. aeruginosa, Klebsiella pneumoniae, and Micrococcus luteus) were detected in gut microbiome samples thus supporting the notion that fish shapes its gut microbiota with changing ecology. Functional profiling showed that microbial communities are specialized in metabolic functions thus reflecting the dietary profile of these invasive fishes.
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Affiliation(s)
- Meghali Bharti
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Shekhar Nagar
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India
- Deshbandhu College, University of Delhi, Delhi, India
| | - Himani Khurana
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Ram Krishan Negi
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi, 110007, India.
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Nagar S, Talwar C, Motelica-Heino M, Richnow HH, Shakarad M, Lal R, Negi RK. Microbial Ecology of Sulfur Biogeochemical Cycling at a Mesothermal Hot Spring Atop Northern Himalayas, India. Front Microbiol 2022; 13:848010. [PMID: 35495730 PMCID: PMC9044081 DOI: 10.3389/fmicb.2022.848010] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 03/09/2022] [Indexed: 11/13/2022] Open
Abstract
Sulfur related prokaryotes residing in hot spring present good opportunity for exploring the limitless possibilities of integral ecosystem processes. Metagenomic analysis further expands the phylogenetic breadth of these extraordinary sulfur (S) metabolizing microorganisms as well as their complex metabolic networks and syntrophic interactions in environmental biosystems. Through this study, we explored and expanded the microbial genetic repertoire with focus on S cycling genes through metagenomic analysis of S contaminated hot spring, located at the Northern Himalayas. The analysis revealed rich diversity of microbial consortia with established roles in S cycling such as Pseudomonas, Thioalkalivibrio, Desulfovibrio, and Desulfobulbaceae (Proteobacteria). The major gene families inferred to be abundant across microbial mat, sediment, and water were assigned to Proteobacteria as reflected from the reads per kilobase (RPKs) categorized into translation and ribosomal structure and biogenesis. An analysis of sequence similarity showed conserved pattern of both dsrAB genes (n = 178) retrieved from all metagenomes while other S disproportionation proteins were diverged due to different structural and chemical substrates. The diversity of S oxidizing bacteria (SOB) and sulfate reducing bacteria (SRB) with conserved (r)dsrAB suggests for it to be an important adaptation for microbial fitness at this site. Here, (i) the oxidative and reductive dsr evolutionary time-scale phylogeny proved that the earliest (but not the first) dsrAB proteins belong to anaerobic Thiobacillus with other (rdsr) oxidizers, also we confirm that (ii) SRBs belongs to δ-Proteobacteria occurring independent lateral gene transfer (LGT) of dsr genes to different and few novel lineages. Further, the structural prediction of unassigned DsrAB proteins confirmed their relatedness with species of Desulfovibrio (TM score = 0.86, 0.98, 0.96) and Archaeoglobus fulgidus (TM score = 0.97, 0.98). We proposed that the genetic repertoire might provide the basis of studying time-scale evolution and horizontal gene transfer of these genes in biogeochemical S cycling.
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Affiliation(s)
- Shekhar Nagar
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, New Delhi, India
| | - Chandni Talwar
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, New Delhi, India
| | - Mikael Motelica-Heino
- UMR 7327, Centre National de la Recherche Scientifique, Institut des Sciences de la Terre D'Orleans (ISTO), Université d'Orleans-Brgm, Orleans, France
| | - Hans-Hermann Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Mallikarjun Shakarad
- Evolutionary Biology Laboratory, Department of Zoology, University of Delhi, New Delhi, India
| | - Rup Lal
- NASI Senior Scientist Platinum Jubilee Fellow, The Energy and Resources Institute, New Delhi, India
| | - Ram Krishan Negi
- Fish Molecular Biology Laboratory, Department of Zoology, University of Delhi, New Delhi, India
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Faridmoayer JRE, Lapkus M, Pastewski J, Sun F, Elassar H, Studzinski D, Czako P, Nagar S, Chen H. VASCULAR INVASION PREDICTS ADVANCED TUMOR CHARACTERISTICS IN PAPILLARY THYROID CARCINOMA. Am J Surg 2022; 223:492. [DOI: 10.1016/j.amjsurg.2022.02.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Nagar S, Talwar C, Bharti M, Yadav S, Siwach S, Negi RK. Metagenome-assembled genomes recovered from the datasets of a high-altitude Himalayan hot spring Khirganga, Himachal Pradesh, India. Data Brief 2021; 39:107551. [PMID: 34825025 PMCID: PMC8603008 DOI: 10.1016/j.dib.2021.107551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/28/2021] [Accepted: 11/01/2021] [Indexed: 11/24/2022] Open
Abstract
Khirganga, a pristine hot spring that lies in the Parvati Valley within the Northern Himalayas characterised with unique white colour microbial mat and divine water with healing abilities. Here, we report 41 metagenome-assembled genomes (MAGs) reconstructed from the microbial mat, sediment and water samples of hot spring passed through Genome Standards Consortium (GSC) and Minimum Information of Metagenome-assembled Genome (MIMAG).
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Affiliation(s)
- Shekhar Nagar
- Department of Zoology, University of Delhi, Delhi 110007, India
| | - Chandni Talwar
- Department of Zoology, University of Delhi, Delhi 110007, India
| | - Meghali Bharti
- Department of Zoology, University of Delhi, Delhi 110007, India
| | - Sheetal Yadav
- Department of Zoology, University of Delhi, Delhi 110007, India
| | - Sneha Siwach
- Department of Zoology, University of Delhi, Delhi 110007, India
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Dhingra GG, Saxena A, Nigam A, Hira P, Singhvi N, Anand S, Kaur J, Kaur J, Dua A, Negi V, Gupta V, Sood U, Kumar R, Lal S, Verma H, Verma M, Singh P, Rawat CD, Tripathi C, Talwar C, Nagar S, Mahato NK, Prakash O, Singh M, Kuhad RC, Singh Y, Lal B, Pabbi S, Singh N, Kalia VC, Lal R. Microbial World: Recent Developments in Health, Agriculture and Environmental Sciences: An Annual Conference Organized by Association of Microbiologists of India and Indian Network for Soil Contamination Research. Indian J Microbiol 2021; 61:111-115. [PMID: 33814643 PMCID: PMC8006636 DOI: 10.1007/s12088-021-00931-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
| | - Anjali Saxena
- Bhaskaracharya College of Applied Sciences, University of Delhi, Delhi, India
| | - Aeshna Nigam
- Shivaji College, University of Delhi, Delhi, India
| | - Princy Hira
- Maitreyi College, University of Delhi, Delhi, India
| | | | - Shailly Anand
- Deen Dyal Upadhyaya College, University of Delhi, Delhi, India
| | - Jasvinder Kaur
- Gargi College, Siri Fort Road, University of Delhi, Delhi, India
| | | | - Ankita Dua
- Shivaji College, University of Delhi, Delhi, India
| | - Vivek Negi
- Sri Aurobindo College, University of Delhi, Delhi, India
| | - Vipin Gupta
- Phixgen Pvt. Ltd, Noida, Uttar Pradesh India
| | - Utkarsh Sood
- The Energy and Resources Institute, Delhi, India
| | - Roshan Kumar
- Department of Zoology, Magadh University, Bodh Gaya, Bihar, India
| | - Sukanya Lal
- Ramjas College, University of Delhi, Delhi, India
| | | | - Mansi Verma
- Sri Venketeshwara College, University of Delhi, Delhi, India
| | - Priya Singh
- Maitreyi College, University of Delhi, Delhi, India
| | | | - Charu Tripathi
- Department of Zoology, CMP College, University of Allahabad, Prayagraj, India
| | - Chandni Talwar
- Department of Zoology, University of Delhi, Delhi, India
| | - Shekhar Nagar
- Department of Zoology, University of Delhi, Delhi, India
| | | | - Om Prakash
- National Centre for Cell Sciences, Pune, Maharashtra India
| | - Mona Singh
- Phixgen Pvt. Ltd, Noida, Uttar Pradesh India
| | - R C Kuhad
- Vice-Chancellor, Central University of Haryana, Mahendragarh, Haryana India
| | - Yogendra Singh
- Department of Zoology, University of Delhi, Delhi, India
| | - Banwari Lal
- The Energy and Resources Institute, Delhi, India
| | - Sunil Pabbi
- ICAR-Indian Agricultural Research Institute, Delhi, India
| | - Namita Singh
- Guru Jambheshwar University of Science and Technology, Hisar, Haryana India
| | - V C Kalia
- Konkuk University, Seoul, Republic of Korea
| | - Rup Lal
- The Energy and Resources Institute, Delhi, India
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Verma H, Nagar S, Vohra S, Pandey S, Lal D, Negi RK, Lal R, Rawat CD. Genome analyses of 174 strains of Mycobacterium tuberculosis provide insight into the evolution of drug resistance and reveal potential drug targets. Microb Genom 2021; 7:mgen000542. [PMID: 33750515 PMCID: PMC8190606 DOI: 10.1099/mgen.0.000542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 02/09/2021] [Indexed: 12/16/2022] Open
Abstract
Mycobacterium tuberculosis is a known human pathogen that causes the airborne infectious disease tuberculosis (TB). Every year TB infects millions of people worldwide. The emergence of multi-drug resistant (MDR), extensively drug resistant (XDR) and totally drug resistant (TDR) M. tuberculosis strains against the first- and second-line anti-TB drugs has created an urgent need for the development and implementation of new drug strategies. In this study, the complete genomes of 174 strains of M. tuberculosis are analysed to understand the evolution of molecular drug target (MDT) genes. Phylogenomic placements of M. tuberculosis strains depicted close association and temporal clustering. Selection pressure analysis by deducing the ratio of non-synonymous to synonymous substitution rates (dN/dS) in 51 MDT genes of the 174 M. tuberculosis strains led to categorizing these genes into diversifying (D, dN/dS>0.70), moderately diversifying (MD, dN/dS=0.35-0.70) and stabilized (S, dN/dS<0.35) genes. The genes rpsL, gidB, pncA and ahpC were identified as diversifying, and Rv0488, kasA, ndh, ethR, ethA, embR and ddn were identified as stabilized genes. Furthermore, sequence similarity networks were drawn that supported these divisions. In the multiple sequence alignments of diversifying and stabilized proteins, previously reported resistance mutations were checked to predict sensitive and resistant strains of M. tuberculosis. Finally, to delineate the potential of stabilized or least diversified genes/proteins as anti-TB drug targets, protein-protein interactions of MDT proteins with human proteins were analysed. We predict that kasA (dN/dS=0.29), a stabilized gene that encodes the most host-interacting protein, KasA, should serve as a potential drug target for the treatment of TB.
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Affiliation(s)
- Helianthous Verma
- Molecular Biology and Genomics Research Laboratory, Ramjas College, University of Delhi, Delhi 110007, India
- Department of Zoology, Ramjas College, University of Delhi, Delhi 110007, India
| | - Shekhar Nagar
- Department of Zoology, University of Delhi, Delhi 110007, India
| | - Shivani Vohra
- Department of Zoology, Ramjas College, University of Delhi, Delhi 110007, India
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi 110021, India
| | - Shubhanshu Pandey
- Department of Zoology, Ramjas College, University of Delhi, Delhi 110007, India
- Department of Biotechnology, Jamia Millia Islamia, Okhla, New Delhi 110025, India
| | - Devi Lal
- Department of Zoology, Ramjas College, University of Delhi, Delhi 110007, India
| | | | - Rup Lal
- The Energy and Resources Institute, Darbari Seth Block, IHC Complex, Lodhi Road, New Delhi 110003, India
| | - Charu Dogra Rawat
- Molecular Biology and Genomics Research Laboratory, Ramjas College, University of Delhi, Delhi 110007, India
- Department of Zoology, Ramjas College, University of Delhi, Delhi 110007, India
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Liu J, Obaidi I, Nagar S, Scalabrino G, Sheridan H. The antiviral potential of algal-derived macromolecules. Current Research in Biotechnology 2021. [DOI: 10.1016/j.crbiot.2021.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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15
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Nagar S, Talwar C, Haider S, Puri A, Ponnusamy K, Gupta M, Sood U, Bajaj A, Lal R, Kumar R. Phylogenetic Relationships and Potential Functional Attributes of the Genus Parapedobacter: A Member of Family Sphingobacteriaceae. Front Microbiol 2020; 11:1725. [PMID: 33013721 PMCID: PMC7500135 DOI: 10.3389/fmicb.2020.01725] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 06/30/2020] [Indexed: 11/28/2022] Open
Abstract
The genus Parapedobacter was established to describe a novel genus within the family Sphingobacteriaceae and derives its name from Pedobacter, with which it is shown to be evolutionarily related. Despite this, Parapedobacter and Pedobacter do not share very high 16S rRNA gene sequence similarities. Therefore, we hypothesized whether these substantial differences at the 16S rRNA gene level depict the true phylogeny or that these genomes have actually diverged. Thus, we performed genomic analysis of the four available genomes of Parapedobacter to better understand their phylogenomic position within family Sphingobacteriaceae. Our results demonstrated that Parapedobacter is more closely related to species of Olivibacter, as opposed to the genus Pedobacter. Further, we identified a significant class of enzymes called pectinases with potential industrial applications within the genomes of Parapedobacter luteus DSM 22899T and Parapedobacter composti DSM 22900T. These enzymes, specifically pectinesterases and pectate lyases, are presumed to have largely different catalytic activities based on very low sequence similarities to already known enzymes and thus may be exploited for industrial applications. We also determined the complete Bacteroides aerotolerance (Bat) operon (batA, batB, batC, batD, batE, hypothetical protein, moxR, and pa3071) within the genome of Parapedobacter indicus RK1T. This expands the definition of genus Parapedobacter to containing members that are able to tolerate oxygen stress using encoded oxidative stress responsive systems. By conducting a signal propagation network analysis, we determined that BatD, BatE, and hypothetical proteins are the major controlling hubs that drive the expression of Bat operon. As a key metabolic difference, we also annotated the complete iol operon within the P. indicus RK1T genome for utilization of all three stereoisomers of inositol, namely myo-inositol, scyllo-inositol, and 1D-chiro-inositol, which are abundant sources of organic phosphate found in soils. The results suggest that the genus Parapedobacter holds promising applications owing to its environmentally relevant genomic adaptations, which may be exploited in the future.
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Affiliation(s)
- Shekhar Nagar
- Department of Zoology, University of Delhi, Delhi, India
| | - Chandni Talwar
- Department of Zoology, University of Delhi, Delhi, India
| | - Shazia Haider
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida, India
| | - Akshita Puri
- Department of Zoology, University of Delhi, Delhi, India.,P.G.T.D, Zoology, R.T.M Nagpur University, Nagpur, India
| | | | - Madhuri Gupta
- Department of Zoology, University of Delhi, Delhi, India
| | - Utkarsh Sood
- Department of Zoology, University of Delhi, Delhi, India.,The Energy and Resources Institute, New Delhi, India
| | - Abhay Bajaj
- Department of Zoology, University of Delhi, Delhi, India.,Environmental Biotechnology and Genomics Division, CSIR-National Environmental Engineering Research Institute, Nagpur, India
| | - Rup Lal
- Department of Zoology, University of Delhi, Delhi, India.,The Energy and Resources Institute, New Delhi, India
| | - Roshan Kumar
- Department of Zoology, University of Delhi, Delhi, India.,P.G. Department of Zoology, Magadh University, Bodh Gaya, India
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Kumar R, Verma H, Singhvi N, Sood U, Gupta V, Singh M, Kumari R, Hira P, Nagar S, Talwar C, Nayyar N, Anand S, Rawat CD, Verma M, Negi RK, Singh Y, Lal R. Comparative Genomic Analysis of Rapidly Evolving SARS-CoV-2 Reveals Mosaic Pattern of Phylogeographical Distribution. mSystems 2020; 5:e00505-20. [PMID: 32723797 PMCID: PMC7394360 DOI: 10.1128/msystems.00505-20] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 07/14/2020] [Indexed: 02/07/2023] Open
Abstract
The outbreak of coronavirus disease 2019 (COVID-19) that started in Wuhan, China, in December 2019 has spread worldwide, emerging as a global pandemic. The severe respiratory pneumonia caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has so far claimed more than 0.38 million lives and has impacted human lives worldwide. However, as the novel SARS-CoV-2 virus displays high transmission rates, the underlying genomic severity is required to be fully understood. We studied the complete genomes of 95 SARS-CoV-2 strains from different geographical regions worldwide to uncover the pattern of the spread of the virus. We show that there is no direct transmission pattern of the virus among neighboring countries, suggesting that its spread is a result of travel of infected humans to different countries. We revealed unique single nucleotide polymorphisms (SNPs) in nonstructural protein 13 (nsp13), nsp14, nsp15, and nsp16 (ORF1b polyproteins) and in the S-protein within 10 viral isolates from the United States. These viral proteins are involved in RNA replication and binding with the human receptors, indicating that the viral variants that are circulating in the population of the United States are different from those circulating in the populations of other countries. In addition, we found an amino acid addition in nsp16 (mRNA cap-1 methyltransferase) of a U.S. isolate (GenBank accession no. MT188341.1) leading to a shift in the amino acid frame from position 2540 onward. Through comparative structural analysis of the wild-type and mutant proteins, we showed that this addition of a phenylalanine residue renders the protein in the mutant less stable, which might affect mRNA cap-1 methyltransferase function. We further analyzed the SARS-CoV-2-human interactome, which revealed that the interferon signaling pathway is targeted by orf1ab during infection and that it also interacts with NF-κB-repressing factor (NKRF), which is a potential regulator of interleukin-8 (IL-8). We propose that targeting this interaction may subsequently improve the health condition of COVID-19 patients. Our analysis also emphasized that SARS-CoV-2 manipulates spliceosome machinery during infection; hence, targeting splicing might affect viral replication. In conclusion, the replicative machinery of SARS-CoV-2 is targeting interferon and the notch signaling pathway along with spliceosome machinery to evade host challenges.IMPORTANCE The COVID-19 pandemic continues to storm the world, with over 6.5 million cases worldwide. The severity of the disease varies with the territories and is mainly influenced by population density and age factor. In this study, we analyzed the transmission pattern of 95 SARS-CoV-2 genomes isolated from 11 different countries. Our study also revealed several nonsynonymous mutations in ORF1b and S-proteins and the impact on their structural stability. Our analysis showed the manipulation of host system by viral proteins through SARS-CoV-2-human protein interactome, which can be useful to understand the impact of virus on human health.
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Affiliation(s)
- Roshan Kumar
- P.G. Department of Zoology, Magadh University, Bodh Gaya, Bihar, India
| | - Helianthous Verma
- Department of Zoology, Ramjas College, University of Delhi, Delhi, India
| | | | - Utkarsh Sood
- The Energy and Resources Institute, New Delhi, India
| | - Vipin Gupta
- PhiXGen Private Limited, Gurugram, Haryana, India
| | - Mona Singh
- PhiXGen Private Limited, Gurugram, Haryana, India
| | - Rashmi Kumari
- Department of Zoology, College of Commerce, Arts & Science, Patliputra University, Patna, Bihar, India
| | - Princy Hira
- Department of Zoology, Maitreyi College, University of Delhi, New Delhi, India
| | - Shekhar Nagar
- Department of Zoology, University of Delhi, Delhi, India
| | - Chandni Talwar
- Department of Zoology, University of Delhi, Delhi, India
| | - Namita Nayyar
- Department of Zoology, Sri Venkateswara College, University of Delhi, New Delhi, India
| | - Shailly Anand
- Department of Zoology, Deen Dayal Upadhyaya College, University of Delhi, New Delhi, India
| | - Charu Dogra Rawat
- Department of Zoology, Ramjas College, University of Delhi, Delhi, India
| | - Mansi Verma
- Department of Zoology, Sri Venkateswara College, University of Delhi, New Delhi, India
| | | | - Yogendra Singh
- Department of Zoology, University of Delhi, Delhi, India
| | - Rup Lal
- The Energy and Resources Institute, New Delhi, India
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17
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Davidson I, Altory-Natour A, Haddas R, Nagar S, Meir R, Avital-Cohen N, Rozenboim I. Evaluation of Viral-Induced Stress by Quantitating Corticosterone in Feathers of Virus-Infected Specific Pathogen-Free Chicks. J APPL POULTRY RES 2020. [DOI: 10.3382/japr/pfz027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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18
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Talwar C, Nagar S, Lal R, Negi RK. Fish Gut Microbiome: Current Approaches and Future Perspectives. Indian J Microbiol 2018; 58:397-414. [PMID: 30262950 DOI: 10.1007/s12088-018-0760-y] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 08/17/2018] [Indexed: 12/13/2022] Open
Abstract
In recent years, investigations of microbial flora associated with fish gut have deepened our knowledge of the complex interactions occurring between microbes and host fish. The gut microbiome not only reinforces the digestive and immune systems in fish but is itself shaped by several host-associated factors. Unfortunately, in the past, majority of studies have focused upon the structure of fish gut microbiome providing little knowledge of effects of these factors distinctively and the immense functional potential of the gut microbiome. In this review, we have highlighted the recently gained insights into the diversity and functions of the fish gut microbiome. We have also delved on the current approaches that are being employed to study the fish gut microbiome with an aim to collate all the knowledge gained and make accurate conclusions for their application based perspectives. The literature reviewed indicated that the future research should shift towards functional microbiomics to improve the maximum sustainable yield in aquaculture.
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Affiliation(s)
- Chandni Talwar
- Department of Zoology, University of Delhi, Delhi, 110007 India
| | - Shekhar Nagar
- Department of Zoology, University of Delhi, Delhi, 110007 India
| | - Rup Lal
- Department of Zoology, University of Delhi, Delhi, 110007 India
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19
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Brufsky A, Davis K, Mitra D, Nagar S, McRoy L, Cotter M, Stearns V. Abstract P5-21-24: Retrospective assessment of treatment patterns and outcomes associated with palbociclib plus letrozole for postmenopausal women with HR+/HER2– advanced breast cancer enrolled in an early access program. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-p5-21-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: The objective of this study was to evaluate treatment patterns and clinical outcomes among patients who received palbociclib in combination with letrozole (P+L) for the treatment of HR+/HER2–advanced breast cancer (ABC) as part of an Expanded Access Program (EAP) in the United States.
Methods: Data were obtained by a retrospective chart review of patients previously enrolled in the EAP. Complete data from time of initial diagnosis of ABC until the date of chart abstraction (end of follow-up), including the post-EAP period, were obtained. Clinical outcomes assessed included clinical benefit rate (CBR), defined as complete response, partial response, or stable disease for ≥24 weeks from P + L initiation, progression free survival (PFS) and overall survival (OS). Survival outcomes were assessed using the Kaplan-Meier statistical analysis.
Results: Data from 126 patients were included in this analysis. Median age was 62.5 years at EAP enrollment, and a majority of patients were Caucasian (83%). Approximately 25% of patients had de novo metastatic disease. A majority of patients had a performance status of ECOG 0 (56%) or 1 (37%) at EAP enrollment. Visceral disease was present in 71% of patients and 16% had bone-only disease. The majority of patients in this cohort from the EAP were heavily pre-treated, having had up to 5 prior lines of therapy in the metastatic setting prior to initiating P + L therapy; nearly 59% received 3+ prior lines before initiating P + L. Only 11% of patients received P + L as their initial regimen for MBC. At the time of the last available record, 12 patients were still on P + L therapy, an average of 21 months after the start of the EAP program. Nearly 80% of patients had prior AI exposure and 69% had prior chemotherapy. CBR was 33% for the overall sample of patients treated with P + L and 22% in those with 3+ prior lines of treatment. Patients with prior AI exposure in the ABC setting (n=100) had a CBR of 27% while those without prior AI exposure had CBR of 58%. Patients with prior chemotherapy (n=87) had a CBR of 28% and those without prior chemotherapy had CBR of 46%. For the entire cohort, 6- and 12-month PFS rates were 40% and 25% respectively; 12- and 24-month OS rates were 66% and 44%, respectively. Patients receiving 3+ lines of prior therapy had 6- and 12-month PFS rates of 28% and 19%, respectively, and 12- and 24-month OS rates of 59% and 34% respectively.
Conclusions: Our results suggest that the majority of patients enrolled in the EAP program derived benefit from receiving treatment with P + L despite multiple prior lines of treatment and prior endocrine-based therapy, including prior AI. These findings further demonstrate the benefit of treatment with palbociclib combination therapy in HR+/HER2– MBC.
Citation Format: Brufsky A, Davis K, Mitra D, Nagar S, McRoy L, Cotter M, Stearns V. Retrospective assessment of treatment patterns and outcomes associated with palbociclib plus letrozole for postmenopausal women with HR+/HER2– advanced breast cancer enrolled in an early access program [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-21-24.
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Affiliation(s)
- A Brufsky
- University of Pittsburgh Medical Center; RTI Health Solutions; Pfizer, Inc.; Johns Hopkins Sidney Kimmel Comprehensive Cancer Center
| | - K Davis
- University of Pittsburgh Medical Center; RTI Health Solutions; Pfizer, Inc.; Johns Hopkins Sidney Kimmel Comprehensive Cancer Center
| | - D Mitra
- University of Pittsburgh Medical Center; RTI Health Solutions; Pfizer, Inc.; Johns Hopkins Sidney Kimmel Comprehensive Cancer Center
| | - S Nagar
- University of Pittsburgh Medical Center; RTI Health Solutions; Pfizer, Inc.; Johns Hopkins Sidney Kimmel Comprehensive Cancer Center
| | - L McRoy
- University of Pittsburgh Medical Center; RTI Health Solutions; Pfizer, Inc.; Johns Hopkins Sidney Kimmel Comprehensive Cancer Center
| | - M Cotter
- University of Pittsburgh Medical Center; RTI Health Solutions; Pfizer, Inc.; Johns Hopkins Sidney Kimmel Comprehensive Cancer Center
| | - V Stearns
- University of Pittsburgh Medical Center; RTI Health Solutions; Pfizer, Inc.; Johns Hopkins Sidney Kimmel Comprehensive Cancer Center
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20
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Mahato NK, Gupta V, Singh P, Kumari R, Verma H, Tripathi C, Rani P, Sharma A, Singhvi N, Sood U, Hira P, Kohli P, Nayyar N, Puri A, Bajaj A, Kumar R, Negi V, Talwar C, Khurana H, Nagar S, Sharma M, Mishra H, Singh AK, Dhingra G, Negi RK, Shakarad M, Singh Y, Lal R. Microbial taxonomy in the era of OMICS: application of DNA sequences, computational tools and techniques. Antonie Van Leeuwenhoek 2017; 110:1357-1371. [PMID: 28831610 DOI: 10.1007/s10482-017-0928-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 08/10/2017] [Indexed: 02/06/2023]
Abstract
The current prokaryotic taxonomy classifies phenotypically and genotypically diverse microorganisms using a polyphasic approach. With advances in the next-generation sequencing technologies and computational tools for analysis of genomes, the traditional polyphasic method is complemented with genomic data to delineate and classify bacterial genera and species as an alternative to cumbersome and error-prone laboratory tests. This review discusses the applications of sequence-based tools and techniques for bacterial classification and provides a scheme for more robust and reproducible bacterial classification based on genomic data. The present review highlights promising tools and techniques such as ortho-Average Nucleotide Identity, Genome to Genome Distance Calculator and Multi Locus Sequence Analysis, which can be validly employed for characterizing novel microorganisms and assessing phylogenetic relationships. In addition, the review discusses the possibility of employing metagenomic data to assess the phylogenetic associations of uncultured microorganisms. Through this article, we present a review of genomic approaches that can be included in the scheme of taxonomy of bacteria and archaea based on computational and in silico advances to boost the credibility of taxonomic classification in this genomic era.
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Affiliation(s)
| | - Vipin Gupta
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Priya Singh
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Rashmi Kumari
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | | | - Charu Tripathi
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Pooja Rani
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Anukriti Sharma
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Nirjara Singhvi
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Utkarsh Sood
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Princy Hira
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Puneet Kohli
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Namita Nayyar
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Akshita Puri
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Abhay Bajaj
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Roshan Kumar
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Vivek Negi
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Chandni Talwar
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Himani Khurana
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Shekhar Nagar
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Monika Sharma
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Harshita Mishra
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Amit Kumar Singh
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Gauri Dhingra
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Ram Krishan Negi
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | | | - Yogendra Singh
- Department of Zoology, University of Delhi, Delhi, 110007, India
| | - Rup Lal
- Department of Zoology, University of Delhi, Delhi, 110007, India.
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22
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Youssef AS, Parkman HP, Nagar S. Drug-drug interactions in pharmacologic management of gastroparesis. Neurogastroenterol Motil 2015; 27:1528-41. [PMID: 26059917 DOI: 10.1111/nmo.12614] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 05/13/2015] [Indexed: 02/08/2023]
Abstract
BACKGROUND Gastroparesis is a disorder characterized by delayed gastric emptying due to chronic abnormal gastric motility. The treatment of the disease often entails the co-administration of several classes of pharmacological agents. These agents may be metabolized via the same pathway. Inhibition or induction of a shared metabolic pathway leads to change in the systemic levels of prescribed drugs, possibly leading to undesired clinical outcomes. PURPOSE This review discusses different pharmacological treatment for gastroparesis patients and describes the potential for drug-drug interactions (DDIs) in some of the combinations that are currently used. Prokinetic agents such as metoclopramide and domperidone are the cornerstone in treatment of gastroparesis. Antiemetic agents such as promethazine and ondansetron are frequently administered to gastroparesis patients to reduce nausea and vomiting. Gastroparesis is prevalent in diabetic patients and therefore antidiabetic agents are also prescribed. Many of these co-administered drugs are metabolized via common drug metabolizing enzymes and this can trigger potential DDIs. The scientific literature was reviewed from the years 1975-2014 for original research articles and reviews that evaluated DDIs in gastroparesis. Many commonly prescribed combinations were predicted to cause potential DDIs in gastroparesis patients. This review will help inform about potential hazardous combinations. This information will hopefully lead to less adverse effects and more successful gastroparesis management.
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Affiliation(s)
- A S Youssef
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, PA, USA
| | - H P Parkman
- Gastroenterology Section, Temple University School of Medicine, Philadelphia, PA, USA
| | - S Nagar
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, PA, USA
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23
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Chu X, Korzekwa K, Elsby R, Fenner K, Galetin A, Lai Y, Matsson P, Moss A, Nagar S, Rosania GR, Bai JPF, Polli JW, Sugiyama Y, Brouwer KLR. Intracellular drug concentrations and transporters: measurement, modeling, and implications for the liver. Clin Pharmacol Ther 2013; 94:126-41. [PMID: 23588320 DOI: 10.1038/clpt.2013.78] [Citation(s) in RCA: 186] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Intracellular concentrations of drugs and metabolites are often important determinants of efficacy, toxicity, and drug interactions. Hepatic drug distribution can be affected by many factors, including physicochemical properties, uptake/efflux transporters, protein binding, organelle sequestration, and metabolism. This white paper highlights determinants of hepatocyte drug/metabolite concentrations and provides an update on model systems, methods, and modeling/simulation approaches used to quantitatively assess hepatocellular concentrations of molecules. The critical scientific gaps and future research directions in this field are discussed.
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Affiliation(s)
- X Chu
- Department of Pharmacokinetics, Pharmacodynamics and Drug Metabolism, Merck & Co., Rahway, New Jersey, USA.
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Zamek-Gliszczynski MJ, Lee CA, Poirier A, Bentz J, Chu X, Ellens H, Ishikawa T, Jamei M, Kalvass JC, Nagar S, Pang KS, Korzekwa K, Swaan PW, Taub ME, Zhao P, Galetin A. ITC recommendations for transporter kinetic parameter estimation and translational modeling of transport-mediated PK and DDIs in humans. Clin Pharmacol Ther 2013; 94:64-79. [PMID: 23588311 DOI: 10.1038/clpt.2013.45] [Citation(s) in RCA: 151] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
This white paper provides a critical analysis of methods for estimating transporter kinetics and recommendations on proper parameter calculation in various experimental systems. Rational interpretation of transporter-knockout animal findings and application of static and dynamic physiologically based modeling approaches for prediction of human transporter-mediated pharmacokinetics and drug-drug interactions (DDIs) are presented. The objective is to provide appropriate guidance for the use of in vitro, in vivo, and modeling tools in translational transporter science.
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Affiliation(s)
- M J Zamek-Gliszczynski
- Drug Disposition, Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, Indiana, USA
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Harned J, Ferrell J, Nagar S, Goralska M, Fleisher LN, McGahan MC. Ceruloplasmin alters intracellular iron regulated proteins and pathways: ferritin, transferrin receptor, glutamate and hypoxia-inducible factor-1α. Exp Eye Res 2012; 97:90-7. [PMID: 22343016 DOI: 10.1016/j.exer.2012.02.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 01/11/2012] [Accepted: 02/02/2012] [Indexed: 11/16/2022]
Abstract
Ceruloplasmin (Cp) is a ferroxidase important to the regulation of both systemic and intracellular iron levels. Cp has a critical role in iron metabolism in the brain and retina as shown in patients with aceruloplasminemia and in Cp-/-hep-/y mice where iron accumulates and neural and retinal degeneration ensue. We have previously shown that cultured lens epithelial cells (LEC) secrete Cp. The purpose of the current study was to determine if cultured retinal pigmented epithelial cells (RPE) also secrete Cp. In addition, the effects of exogenously added Cp on iron regulated proteins and pathways, ferritin, transferrin receptor, glutamate secretion and levels of hypoxia-inducible factor-1α in the nucleus were determined. Like LEC, RPE secrete Cp. Cp was found diffusely distributed within both cultured LEC and RPE, but the cell membranes had more intense staining. Exogenously added Cp caused an increase in ferritin levels in both cell types and increased secretion of glutamate. The Cp-induced increase in glutamate secretion was inhibited by both the aconitase inhibitor oxalomalic acid as well as iron chelators. As predicted by the canonical view of the iron regulatory protein (IRP) as the predominant controller of cellular iron status these results indicate that there is an increase in available iron (called the labile iron pool (LIP)) in the cytoplasm. However, both transferrin receptor (TfR) and nuclear levels of HIF-1α were increased and these results point to a decrease in available iron. Such confounding results have been found in other systems and indicate that there is a much more complex regulation of intracellularly available iron (LIP) and its downstream effects on cell metabolism. Importantly, the Cp increased production and secretion of the neurotransmitter, glutamate, is a substantive finding of clinical relevance because of the neural and retinal degeneration found in aceruloplasminemia patients. This finding and Cp-induced nuclear translocation of the hypoxia-inducible factor-1 (HIF1) subunit HIF-1α adds novel information to the list of critical pathways impacted by Cp.
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Affiliation(s)
- J Harned
- Department of Molecular Biomedical Sciences, North Carolina State University, 4700 Hillsborough St., Raleigh, NC 27606, USA
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Toussaint K, Yang XC, Zielinski MA, Reigle KL, Sacavage SD, Nagar S, Raffa RB. What do we (not) know about how paracetamol (acetaminophen) works? J Clin Pharm Ther 2011; 35:617-38. [PMID: 21054454 DOI: 10.1111/j.1365-2710.2009.01143.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
WHAT IS KNOWN AND BACKGROUND Although paracetamol (acetaminophen), N-(4-Hydroxyphenyl)acetamide, is one of the world's most widely used analgesics, the mechanism by which it produces its analgesic effect is largely unknown. This lack is relevant because: (i) optimal pain treatment matches the analgesic mechanism to the (patho)physiology of the pain and (ii) modern drug discovery relies on an appropriate screening assay. OBJECTIVE To review the clinical profile and preclinical studies of paracetamol as means of gaining insight into its mechanism of analgesic action. METHODS A literature search was conducted of clinical and preclinical literature and the information obtained was organized and reviewed from the perspective of its contribution to an understanding of the mechanism of analgesic action of paracetamol. RESULTS Paracetamol's broad spectrum of analgesic and other pharmacological actions is presented, along with its multiple postulated mechanism(s) of action. No one mechanism has been definitively shown to account for its analgesic activity. WHAT IS NEW AND CONCLUSION Further research is needed to uncover the mechanism of analgesic action of paracetamol. The lack of this knowledge affects optimal clinical use and impedes drug discovery efforts.
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Affiliation(s)
- K Toussaint
- Temple University School of Pharmacy, Philadelphia, PA 19140, USA
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Babalola CP, Adejumo O, Ung D, Xu Z, Odetunde A, Kotila T, Falusi AG, Nagar S. Cytochrome P450 CYP2C19 genotypes in Nigerian sickle-cell disease patients and normal controls. J Clin Pharm Ther 2010; 35:471-7. [PMID: 20831548 DOI: 10.1111/j.1365-2710.2009.01122.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND AND OBJECTIVE Subjects with different CYP2C19 genotypes may metabolize proguanil, a pro-drug used for malaria prophylaxis differently and the frequency of the different alleles may be different in patients with sickle-cell disease (SCD) and normal controls. The objective of this study was to evaluate CYP2C19 *1, *2 and *3 allele and genotype frequencies in Nigerian normal controls and SCD patients, and to further compare variant CYP2C19 frequencies in Nigerians with other African populations. METHODS Genotyping was carried out with PCR and restriction fragment length polymorphism analysis. RESULTS AND DISCUSSION CYP2C19 *1 (84·3 vs. 84·9%) or *2 allele frequency (15·7 vs. 15·1%) was not significantly different between patients with SCD and normal subjects. No *3 allele was detected in the cohort. The SCD group exhibited a statistically significantly lower frequency of *1/*1 genotype (69·6%) compared with normal controls (74·4%). Frequency of *2/*2 was significantly lower in SCD (0·9%) compared with normal controls (4·7%). Frequencies of *1/*2 (29·6 vs. 20·9%) were no different in SCD and normal controls. CONCLUSION Prevalence of CYP2C19 polymorphisms was defined for the first time in Nigerian normal and SCD populations. Nigerian SCD patients exhibited significantly lower CYP2C19 *1/*1 and *2/*2 frequencies than normal controls. No differences were detected in CYP2C19 allele or genotype frequencies in normal subjects between this study and previous reports in other African populations.
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Affiliation(s)
- C P Babalola
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ibadan, Ibadan, Oyo State, Nigeria
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Davidson I, Nagar S, Haddas R, Ben-Shabat M, Golender N, Lapin E, Altory A, Simanov L, Ribshtein I, Panshin A, Perk S. Avian influenza virus H9N2 survival at different temperatures and pHs. Avian Dis 2010; 54:725-8. [PMID: 20521722 DOI: 10.1637/8736-032509-resnote.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The H9N2 avian influenza virus (AIV) subtype has become endemic in Israel since its introduction in 2000. The disease has been economically damaging to the commercial poultry industry, in part because of the synergistic pathology of coinfection with other viral and/or bacterial pathogens. Avian influenza virus viability in the environment depends on the cumulative effects of chemical and physical factors, such as humidity, temperature, pH, salinity, and organic compounds, as well as differences in the virus itself. We sought to analyze the viability of AIV H9N2 strains at three temperatures (37, 20, and 4 C) and at 2 pHs (5.0 and 7.0). Our findings indicated that at 37 C AIV H9N2 isolate 1525 (subgroup IV) survived for a period of time 18 times shorter at 20 C, and 70 times shorter period at 4 C, as measured by a decrease in titer. In addition, the virus was sensitive to a lower pH (pH 5.0) with no detectable virus after 1 wk incubation at 20 C as compared to virus at pH 7.0, which was viable for at least 3 wk at that temperature. The temperature sensitivity of the virus corresponds to the occurrence of H9N2 outbreaks during the winter, and lower pH can greatly affect the viability of the virus.
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Affiliation(s)
- I Davidson
- Division of Avian and Fish Diseases, Kimron Veterinary Institute, P.O. Box 12, 50250, Israel.
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Abstract
This study examined in vitro interaction between domperidone and erythromycin. Both are prescribed for refractory gastroparesis. Domperidone is metabolized via human cytochrome P4503A4. Erythromycin is a CYP3A4 inhibitor. Incubations evaluated domperidone metabolite formation in human liver microsomes and recombinant CYP3A4. Concentration- and time-dependent inhibition of 500 microM domperidone was studied with 2.5-200 microM erythromycin over 10-40 min. Domperidone metabolite (5-hydroxy domperidone, M3) formation was inhibited by erythromycin in a concentration- and time-dependent manner. The K(I) estimate was 18.4 microM in human liver microsomes and 4.1 microM in CYP3A4. Using a model incorporating CYP3A4 hepatic and gut inhibition, in vitro estimates from human liver microsomes and CYP3A4 were used to predict in vivo AUCi/AUC ratios of 2.54 and 4.95, respectively. Significant inhibition of domperidone metabolism by erythromycin occurs. This predicts greater domperidone drug exposure when used with erythromycin. This important drug-drug interaction will be evaluated in future human studies.
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Affiliation(s)
- D Ung
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, PA 19140, USA
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Goralska M, Nagar S, Fleisher L, McGahan M. Distribution of ferritin chains in canine lenses with and without age-related nuclear cataracts. Mol Vis 2009; 15:2404-10. [PMID: 19956561 PMCID: PMC2785719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Accepted: 11/04/2009] [Indexed: 11/02/2022] Open
Abstract
PURPOSE It was determined in an earlier study that ferritin-heavy (H) and -light (L) chains in lens fiber cells are modified in comparison to those in lens epithelial cells. The purpose of the present study was to determine whether changes in ferritin chain characteristics are developmental, age-related, or associated with cataractogenesis, by analyzing the distribution of modified chains throughout the lens fiber mass. METHODS After removing the capsule, noncataractous and cataractous lenses were separated into six layers of fiber cells. The content of ferritin H and L chains in each layer was determined by western blotting with chain-specific antibodies. The level of ferritin complex (450 kDa protein made up of assembled L and H chains) was determined using the enzyme-linked immunosorbent assay. The ability of ferritin complex to bind iron was assessed by in vitro labeling with (59)Fe. RESULTS Fiber cell ferritin L chains were 30 kDa (modified from the normal 19 kDa), and were present at the highest level in the outermost layers of both cataractous and non-cataractous lenses. The amount of modified L chains decreased gradually in the inner layers of the fiber mass, and was undetectable in the inner two layers of cataractous lenses. The ferritin H chains were also modified to 12 kDa (perhaps truncated from the normal 21 kDa size) in both cataractous and non-cataractous lenses. Similar levels of this modified H chain were found throughout the normal lens. Interestingly, in cataractous lenses, the modified H chains were found in decreasing amounts towards the interior of the lens, and were undetectable in the nucleus. However, in these cataractous lenses, the normal-sized ferritin H chains (21 kDA) appear in small quantities in the outer fiber layers, and increase in quantity and size (to 29 kDa) in the inner layers. This observation was best seen and demonstrated in advanced cataracts. Ferritin, which can bind iron, was found mainly in the outer layers of the lens fiber mass of normal lenses, but was more evenly distributed in fiber layers from cataractous lenses. CONCLUSIONS Both ferritin H and L chains were modified in lens fiber cells from normal and cataractous canine lenses. These modifications were not age-related, and most likely occur during the differentiation of epithelial cells to fiber cells, since only normal-sized chains have been found in lens epithelial cells. In addition, there was a specific and distinct distribution of these modified chains throughout the lens fiber mass. The most striking differences between normal and cataractous lenses fiber cells were the appearance of normal-sized ferritin H chains and the relatively even distribution of iron binding capacity throughout the fiber mass of the cataractous lenses. These differences may reflect a response of the lens to increased oxidative stress during cataractogenesis.
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Varga LI, Ako-Agugua N, Colasante J, Hertweck L, Houser T, Smith J, Watty AA, Nagar S, Raffa RB. Critical review of ropinirole and pramipexole - putative dopamine D3-receptor selective agonists - for the treatment of RLS. J Clin Pharm Ther 2009; 34:493-505. [DOI: 10.1111/j.1365-2710.2009.01025.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Dhami H, Fritz CE, Gankin B, Pak SH, Yi W, Seya MJ, Raffa RB, Nagar S. The chemokine system and CCR5 antagonists: potential in HIV treatment and other novel therapies. J Clin Pharm Ther 2009; 34:147-60. [PMID: 19250135 DOI: 10.1111/j.1365-2710.2008.00978.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Since the recognition of human acquired immune deficiency syndrome, numerous classes of pharmacologic therapeutics have been developed to manage the disease. Current therapy includes co-administration of combinations of drugs classified by their mechanism of action as 'transcriptase inhibitors', 'protease inhibitors', 'integrase inhibitors' and the more recent 'fusion inhibitors'. This review focuses on the chemokine system and the recognition of chemokine receptors as targets for anti-human immunodeficiency virus (HIV) therapy. The FDA-approved chemokine (C-C motif) receptor 5 (CCR5) antagonist maraviroc (Selzentry) is discussed in detail, along with another compound vicriviroc, currently in clinical trials. The mechanism of action, pharmacokinetics, toxicity and current status of research on CCR5 antagonists is described. Further, potential therapeutic uses of these agents other than anti-HIV therapy are discussed.
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Affiliation(s)
- H Dhami
- Temple University School of Pharmacy, Philadelphia, PA, USA
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Adar Y, Singer Y, Levi R, Tzehoval E, Perk S, Banet-Noach C, Nagar S, Arnon R, Ben-Yedidia T. A universal epitope-based influenza vaccine and its efficacy against H5N1. Vaccine 2009; 27:2099-107. [DOI: 10.1016/j.vaccine.2009.02.011] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Revised: 01/25/2009] [Accepted: 02/02/2009] [Indexed: 01/21/2023]
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Goralska M, Ferrell J, Harned J, Lall M, Nagar S, Fleisher LN, McGahan MC. Iron metabolism in the eye: a review. Exp Eye Res 2009; 88:204-15. [PMID: 19059397 PMCID: PMC3746754 DOI: 10.1016/j.exer.2008.10.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Revised: 10/31/2008] [Accepted: 10/31/2008] [Indexed: 10/21/2022]
Abstract
This review article covers all aspects of iron metabolism, which include studies of iron levels within the eye and the processes used to maintain normal levels of iron in ocular tissues. In addition, the involvement of iron in ocular pathology is explored. In each section there is a short introduction to a specific metabolic process responsible for iron homeostasis, which for the most part has been studied in non-ocular tissues. This is followed by a summary of our current knowledge of the process in ocular tissues.
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Affiliation(s)
- M Goralska
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, NC 27606, USA
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Ung D, Nagar S. Trans-resveratrol-mediated inhibition of β-oestradiol conjugation in MCF-7 cells stably expressing human sulfotransferases SULT1A1 or SULT1E1, and human liver microsomes. Xenobiotica 2009; 39:72-9. [DOI: 10.1080/00498250802604082] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
1. This study examined interactions via common metabolism or via common pharmacodynamic pathways between frequently co-prescribed metoclopramide (a prokinetic) and morphine (an opioid analgesic). 2. In human liver microsomes, morphine 3-glucuronide and morphine 6-glucuronide formation had V(max) estimates of 6.2 +/- 0.07 and 0.75 +/- 0.01 (nmole min(-1) mg(-1) protein) and K(m) estimates of 1080 +/- 37 and 665 +/- 55 (microM), respectively. The in vitro K(i) for morphine 3-glucuronide formation in the presence of metoclopramide in human liver microsomes or recombinant uridine diphosphoglucuronosyltransferase 2B7 predicted a lack of in vivo interaction. 3. Morphine (2 mg kg(-1) subcutaneously) delayed gastrointestinal meal transit in mice, metoclopramide (10 mg kg(-1) subcutaneously) had no effect on meal transit, and metoclopramide did not alter this effect of morphine. 4. Morphine (2 or 5 mg kg(-1) subcutaneously) was antinociceptive in mice (hot plate test) and metoclopramide (10 mg kg(-1) subcutaneously) did not alter the antinociceptive effects of morphine. 5. Together, the data suggest a lack of interaction between morphine and metoclopramide.
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Affiliation(s)
- D Ung
- Pharmaceutical Sciences, Temple University, Philadelphia, PA 19140, USA
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Xie S, Furjanic MA, Ferrara JJ, McAndrew NR, Ardino EL, Ngondara A, Bernstein Y, Thomas KJ, Kim E, Walker JM, Nagar S, Ward SJ, Raffa RB. The endocannabinoid system and rimonabant: a new drug with a novel mechanism of action involving cannabinoid CB1 receptor antagonism--or inverse agonism--as potential obesity treatment and other therapeutic use. J Clin Pharm Ther 2007; 32:209-31. [PMID: 17489873 DOI: 10.1111/j.1365-2710.2007.00817.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
There is considerable evidence that the endocannabinoid (endogenous cannabinoid) system plays a significant role in appetitive drive and associated behaviours. It is therefore reasonable to hypothesize that the attenuation of the activity of this system would have therapeutic benefit in treating disorders that might have a component of excess appetitive drive or over-activity of the endocannabinoid system, such as obesity, ethanol and other drug abuse, and a variety of central nervous system and other disorders. Towards this end, antagonists of cannabinoid receptors have been designed through rational drug discovery efforts. Devoid of the abuse concerns that confound and impede the use of cannabinoid receptor agonists for legitimate medical purposes, investigation of the use of cannabinoid receptor antagonists as possible pharmacotherapeutic agents is currently being actively investigated. The compound furthest along this pathway is rimonabant, a selective CB(1) (cannabinoid receptor subtype 1) antagonist, or inverse agonist, approved in the European Union and under regulatory review in the United States for the treatment of obesity. This article summarizes the basic science of the endocannabinoid system and the therapeutic potential of cannabinoid receptor antagonists, with emphasis on the treatment of obesity.
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Affiliation(s)
- S Xie
- Temple University School of Pharmacy, Philadelphia, PA 19104, USA
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Abstract
The uridine diphosphoglucuronosyltransferases (UGTs) belong to a superfamily of enzymes that catalyse the glucuronidation of numerous endobiotics and xenobiotics. Several human hepatic and extrahepatic UGT isozymes have been characterized with respect to their substrate specificity, tissue expression and gene structure. Genetic polymorphisms have been identified for almost all the UGT family members. A wide variety of anticancer drugs, dietary chemopreventives and carcinogens are known to be conjugated by members of both UGT1A and UGT2B subfamilies. This review examines in detail each UGT isozyme known to be associated with cancer and carcinogenesis. The cancer-related substrates for several UGTs are summarized, and the functionally relevant genetic polymorphisms of UGTs are reviewed. A number of genotype-phenotype association studies have been carried out to characterize the role of UGT pharmacogenetics in several types of cancer, and these examples are discussed here. In summary, this review focuses on the role of the human UGT genetic polymorphisms in carcinogenesis, chemoprevention and cancer risk.
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Affiliation(s)
- S Nagar
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, PA 19140, USA.
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Kramer U, Kipervasser S, Neufeld MY, Fried I, Nagar S, Andelman F. Is there any correlation between severity of epilepsy and cognitive abilities in patients with temporal lobe epilepsy? Eur J Neurol 2006; 13:130-4. [PMID: 16490042 DOI: 10.1111/j.1468-1331.2006.01141.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Frequent refractory seizures may cause cognitive deterioration when they present at an early age, especially in infants. The findings of previous studies designed to examine the impact of repetitive seizures on cognition in adolescents and adults, however, have shown wide variation. We analyzed the data of neuropsychological evaluations of patients before they underwent temporal lobe resection because of refractory seizure disorder in our institution from 1998 to 2001. Forty-four consecutive patients aged 12-48 years underwent a comprehensive neuropsychological evaluation that included a battery of selected visual and verbal memory tests. Statistical analysis revealed no significant correlation between disease-related parameters, such as age of onset, duration of active disease, estimated cumulative number of complex partial seizures and secondarily generalized seizures, and the results of neuropsychological tests. These findings support the hypothesis that factors other than repetitive seizures are responsible for cognitive dysfunction among adolescents and adults.
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Affiliation(s)
- U Kramer
- Functional Neurosurgery Unit, Tel Aviv, Israel.
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Jain AK, Bohra R, Mehrotra RC, Nagar S, Sharma S. Aluminum five- and six-coordination in bis(acetylacetonato)aminoalkoxides. Heteroatom Chem 2003. [DOI: 10.1002/hc.10184] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
OBJECTIVE To determine the relative efficacies of alternative antipneumocystis agents in human immunodeficiency virus (HIV)-infected patients with Pneumocystis carinii pneumonia unresponsive to primary drug treatment with a combination product of trimethoprim and sulfamethoxazole or parenteral pentamidine. METHODS Meta-analysis of 27 published clinical drug trials, case series, and case reports involving P carinii pneumonia. Data extracted included underlying disease, primary antipneumocystis treatment, days of failed primary treatment, salvage regimen, use of systemic corticosteroids and antiretroviral drugs, and clinical outcome. RESULTS In 497 patients with microbiologically confirmed P carinii pneumonia (456 with HIV or acquired immunodeficiency syndrome), initial antipneumocystis treatment failed and they therefore required alternative drug therapy. Failed regimens included trimethoprim-sulfamethoxazole (160 patients), intravenous pentamidine (63 patients), trimethoprim-sulfamethoxazole and/or pentamidine (258 patients), aerosolized pentamidine (6 patients), atovaquone (3 patients), dapsone (3 patients), a combination product of trimethoprim and dapsone (2 patients), and trimethoprim-sulfamethoxazole followed by a combination of clindamycin and primaquine phosphate (2 patients). Efficacies of salvage regimens were as follows: clindamycin-primaquine (42 to 44 [88%-92%] of 48 patients; P<10(-8)), atovaquone (4 [80%] of 5), eflornithine hydrochloride (40 [57%] of 70; P<.01), trimethoprim-sulfamethoxazole (27 [53%] of 51; P<.08), pentamidine (64 [39%] of 164), and trimetrexate (47 [30%] of 159). CONCLUSION The combination of clindamycin plus primaquine appears to be the most effective alternative treatment for patients with P carinii pneumonia who are unresponsive to conventional antipneumocystis agents.
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Affiliation(s)
- R A Smego
- MPH, DTM&H, Department of Medicine, The Aga Khan University Medical College, Stadium Road, PO Box 3500, Karachi 74800, Pakistan
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Abstract
OBJECTIVE To investigate the prevalence of G88C, G209A and any other mutation(s) in exons 3 and 4 of the alpha-synuclein gene in Indian patients with Parkinson's disease (PD). METHODS A total of 169 PD patients comprising 18 familial, 3 juvenile, 48 early onset and 100 sporadic cases were included in this study. Genomic DNA was amplified by PCR using primers specific for Exons 3 and 4. Mutations at G88C and G209A were screened following restriction enzyme digestion of the PCR product. Direct PCR product sequencing of entire exons 3 and 4 was carried out for at least one proband each from the 10 familial cases. RESULTS Neither G88C and G209A mutations nor any other mutation in exons 3 and 4 was found in the PD patients analysed. CONCLUSION The G88C and G209A mutations do not seem to be the predominant genetic determinant of PD among Indians.
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Affiliation(s)
- S Nagar
- Department of Genetics, University of Delhi, New Delhi, India
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Kong LJ, Orozco BM, Roe JL, Nagar S, Ou S, Feiler HS, Durfee T, Miller AB, Gruissem W, Robertson D, Hanley-Bowdoin L. A geminivirus replication protein interacts with the retinoblastoma protein through a novel domain to determine symptoms and tissue specificity of infection in plants. EMBO J 2000; 19:3485-95. [PMID: 10880461 PMCID: PMC313951 DOI: 10.1093/emboj/19.13.3485] [Citation(s) in RCA: 148] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Geminiviruses replicate in nuclei of mature plant cells after inducing the accumulation of host DNA replication machinery. Earlier studies showed that the viral replication factor, AL1, is sufficient for host induction and interacts with the cell cycle regulator, retinoblastoma (pRb). Unlike other DNA virus proteins, AL1 does not contain the pRb binding consensus, LXCXE, and interacts with plant pRb homo logues (pRBR) through a novel amino acid sequence. We mapped the pRBR binding domain of AL1 between amino acids 101 and 180 and identified two mutants that are differentially impacted for AL1-pRBR interactions. Plants infected with the E-N140 mutant, which is wild-type for pRBR binding, developed wild-type symptoms and accumulated viral DNA and AL1 protein in epidermal, mesophyll and vascular cells of mature leaves. Plants inoculated with the KEE146 mutant, which retains 16% pRBR binding activity, only developed chlorosis along the veins, and viral DNA, AL1 protein and the host DNA synthesis factor, proliferating cell nuclear antigen, were localized to vascular tissue. These results established the importance of AL1-pRBR interactions during geminivirus infection of plants.
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Affiliation(s)
- L J Kong
- Departments of Biochemistry and Botany, North Carolina State University, Raleigh, NC 27695, USA
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Balakrishnarajan MM, Jemmis ED, Gupta S, Mazumdar S, Mukherjee P, Machonkin T, Dubois JL, Cole AP, Hedman B, Hodgson KO, Solomon EI, Stack TDP, Roesky HW, Manoharan PT, Baitalik S, Nag K, Sarkar S, Seshadri R, Felser C, Nixon JF, Katti KV, Pillarsetty N, Kamei H, Bora U, Chaudhuri MK, Dhar SS, Kalita D, Anand BN, Ramanan A, Roy P, Duraisamy T, Sharma S, Ayyappan P, Gupta BD, Kanth VV, Singh V, Suresh E, Boopalan K, Jasra RV, Bhadbhade MM, Naganagowda GA, Ramanathan KV, Gayathri V, Nanjegowda NM, Sengupta P, Ghosh S, Bhattacharjee M, Gupta SS, Datta R, Sastri CV, Easwaramoorthy D, Lakshmi A, Giribabu L, Maiya BG, Reddy PR, Radhika M, Nightingale KF, Srinivasan R, Venkatesan R, Rajendiran TM, Sambasiva Rao P, Bhavana P, Bhyrappa P, Ravikanth M, Kumaraswamy S, Kommana P, Padmaja G, Kumara Swamy KC, Mondal B, Chakraborty S, Lahiri GK, Ray M, Que L, Saxena A, Sampriya N, Brar AS, Shankar R, Sahoo BB, Panday G, Wasthi AA, Chauhan SMS, Wadhwani P, Bandyopadhyay DK, Bandyopadhyay R, Biswas S, Bhattacharyya R, Johis V, Kotkar D, Pathak VS, Swayambhunathan V, Kamat P, Das A, Ghosh PK, Gupta R, Mukherjee R, Walawalkar MG, Pal SK, Krishnan A, Samuelson AG, Das PK, Anantharaman G, Baheti K, Murugavel R, Garg G, Ganguli AK, Suresh M, Prasadarao AV, Neeraj S, Natarajan S, Rao CNR, Vanitha PV, Santhosh PN, Rao CNR, Kumar GG, Munichandraiah N, Ramakrishna TVV, Elias AJ, Vij A, Rajak KK, Rath SP, Dutta S, Bhattacharya PK, Natarajan P, Paul P, Dhanasekaran T, Prakash H, Mangayarkarasi N, Zacharias PS, Srinivasan A, Pushpan SK, Anand VG, Chandrashekar TK, Tripathi P, Som A, Bharadwaj PK, Mathew N, Jagirdar BR, Mandal SK, Naganagowda GA, Krishnamurthy SS, Singh UP, Singh R, Hikichi S, Moro-Oka Y, Sevagapandian S, Nehru K, Athappan PR, Murali M, Palaniandavar M, Singh RB, Mitra S, Reddy PAN, Datta R, Chakravarty AR, Sunkari S, Rajasekharan MV, Shukla AD, Bajaj HC, Das A, Krishnamurthy D, Sathiyendiran M, Murugavel R, Rao KM, Boag NM, Neogi DN, Bhawmick R, Bandyopadhyay P, Thomas AM, Mandal GC, Tiwary SK, Chakravarty AR, Sah AK, Das TM, Wegelius EK, Kolehmainen E, Saarenketo PK, Rissanen K, Rao CP, Warad DU, Satish CD, Bajgur CS, Manonmani J, Narayanan V, Kandaswamy M, Kingston JV, Sundaram GSM, Rao MNS, Rajendiran TM, Kannappan R, Venkatesan R, Rao PS, Bilakhiya AK, Tyagi B, Paul P, Dhar SD, Chaudhuri MK, Ghosh T, Banerjee R, Kureshy RI, Khan NH, Abdi SHR, Patel ST, Iyer P, Jasra RV, Chatterjee D, Mitra A, Mukherjee S, Ganesan V, Ramaraj R, Shunmugasundari T, Thanasekaran P, Rajagopal S, Bohra R, Sharma N, Nagar S, Panda R, Balakrishna MS, Vaidhyanathan R, Natarajan S, Rao CNR, Choudhury A, Natarajan S, Rao CNR, Chakrabarty D, Mahapatra S, Devi MS, Vidyasagar K, Mody HM, Pandya P, Bhatt P, Jasra RV, Padmanabhan M, Mathew T, Shukla AD, Dave PC, Suresh E, Pathak G, Das A, Dastidar P, Mahalakshmi L, Krishnamurthy SS, Nethaji M, Rath N, Mathew N, Jagirdhar B, Gopalan RS, Kulkarni GU, Sridevi S, Narayanan J, Chandrashekar TK, Saha A, Ghosh AK, Majumdar P, Goswami S, Abhyankar RM, Balakrishna MS, Basuli F, Bhattacharya S, Mondal N, Saha MK, Bag B, Mitra S, Pal S, Sangeetha NR, Pal S, Dey M, Saarenketo PK, Kolehmainen E, Rissanen K, Rao CP, Suresh E, Bhadbhade MM, Padmakumar K, Manoharan PT, Vernekar B, Srinivasan BR, Ramesh K, Bharathi DS, Samuelson AG, Lokanath NK, Shridhar MA, Prasad S, Venkatraman NV, Vasudevan S, Mimani T, Patil KC, Tiwari AP, Mukkada BJ, Arunan E, Mathias PC, Abraham B, Karthikeyan B, Pal SK, Samuelson AG, Umapathy S, Panda PK, Krishnan V. Abstract. J CHEM SCI 2000. [DOI: 10.1007/bf02706182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Tomato golden mosaic virus (TGMV) is a geminivirus that replicates its single-stranded DNA genome through double-stranded DNA intermediates in nuclei of differentiated plant cells using host replication machinery. We analyzed the distribution of viral and plant DNA in nuclei of infected leaves using fluorescence in situ hybridization (FISH). TGMV-infected nuclei showed up to a sixfold increase in total volume and displayed a variety of viral DNA accumulation patterns. The most striking viral DNA patterns were bright, discrete intranuclear compartments, but diffuse nuclear localization was also observed. Quantitative and spatial measurements of high resolution 3-dimensional image data revealed that these compartments accounted for 1-18% of the total nuclear volume or 2-45% of the total nuclear FISH signals. In contrast, plant DNA was concentrated around the nuclear periphery. In a significant number of nuclei, the peripheral chromatin was organized as condensed prophase-like fibers. A combination of FISH analysis and indirect immunofluorescence with viral coat protein antibodies revealed that TGMV virions are associated with the viral DNA compartments. However, the coat protein antibodies failed to cross react with some large viral DNA inclusions, suggesting that encapsidation may occur after significant viral DNA accumulation. Infection by a TGMV mutant with a defective coat protein open reading frame resulted in fewer and smaller viral DNA-containing compartments. Nevertheless, nuclei infected with the mutant virus increased in size and in some cases showed chromosome condensation. Together, these results established that geminivirus infection alters nuclear architecture and can induce plant chromatin condensation characteristic of cells arrested in early mitosis.
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Affiliation(s)
- H W Bass
- Department of Biological Science, Florida State University, Tallahassee, FL 32306-4370, USA.
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Hanley-Bowdoin L, Settlage SB, Orozco BM, Nagar S, Robertson D. Geminiviruses: models for plant DNA replication, transcription, and cell cycle regulation. Crit Rev Biochem Mol Biol 2000; 35:105-140. [PMID: 10821479 DOI: 10.1016/s0735-2689(99)00383-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Geminiviruses have small, single-stranded DNA genomes that replicate through double-stranded intermediates in the nuclei of infected plant cells. Viral double-stranded DNA also assembles into minichromosomes and is transcribed in infected cells. Geminiviruses encode only a few proteins for their replication and transcription and rely on host enzymes for these processes. However, most plant cells, which have exited the cell cycle and undergone differentiation, do not contain the replicative enzymes necessary for viral DNA synthesis. To overcome this barrier, geminiviruses induce the accumulation of DNA replication machinery in mature plant cells, most likely by modifying cell cycle and transcriptional controls. In animals, several DNA viruses depend on host replication and transcription machinery and can alter their hosts to create an environment that facilitates efficient viral replication. Analysis of these viruses and their proteins has contributed significantly to our understanding of DNA replication, transcription, and cell cycle regulation in mammalian cells. Geminiviruses have the same potential for plant systems. Plants offer many advantages for these types of studies, including ease of transformation, well-defined cell populations and developmental programs, and greater tolerance of cell cycle perturbation and polyploidy. Our knowledge of the molecular and cellular events that mediate geminivirus infection has increased significantly during recent years. The goal of this review is to summarize recent research addressing geminivirus DNA replication and its integration with transcriptional and cell cycle regulatory processes.
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Affiliation(s)
- L Hanley-Bowdoin
- Department of Biochemistry, North Carolina State University, Raleigh 27695-7622, USA
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48
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Abstract
Geminiviruses have small, single-stranded DNA genomes that replicate through double-stranded intermediates in the nuclei of infected plant cells. Viral double-stranded DNA also assembles into minichromosomes and is transcribed in infected cells. Geminiviruses encode only a few proteins for their replication and transcription and rely on host enzymes for these processes. However, most plant cells, which have exited the cell cycle and undergone differentiation, do not contain the replicative enzymes necessary for viral DNA synthesis. To overcome this barrier, geminiviruses induce the accumulation of DNA replication machinery in mature plant cells, most likely by modifying cell cycle and transcriptional controls. In animals, several DNA viruses depend on host replication and transcription machinery and can alter their hosts to create an environment that facilitates efficient viral replication. Analysis of these viruses and their proteins has contributed significantly to our understanding of DNA replication, transcription, and cell cycle regulation in mammalian cells. Geminiviruses have the same potential for plant systems. Plants offer many advantages for these types of studies, including ease of transformation, well-defined cell populations and developmental programs, and greater tolerance of cell cycle perturbation and polyploidy. Our knowledge of the molecular and cellular events that mediate geminivirus infection has increased significantly during recent years. The goal of this review is to summarize recent research addressing geminivirus DNA replication and its integration with transcriptional and cell cycle regulatory processes.
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Affiliation(s)
- L Hanley-Bowdoin
- Department of Biochemistry, North Carolina State University, Raleigh 27695-7622, USA
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Nagar S, Agrawal PK. Is general surgery going the way of the dinosaur. J Indian Med Assoc 1998; 96:29. [PMID: 9601191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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50
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Abstract
Increases in intracellular phosphatidic acid levels caused by receptor- mediated activation of phospholipase D (PLD) have been implicated in many signal transduction pathways leading to cellular activation. PLD is known to be regulated by several means, including tyrosine kinase activity, increases in Ca2+, receptor-coupled G proteins, small GTP binding proteins, ceramide metabolisms, and protein kinase C. We have investigated a additional regulatory effect on PLD activity involving nucleoside triphosphates (NTPs). A NTP binding protein copurifies with LPD activity from rabbit brains using a GTP-agarose affinity column, and this protein stimulates PLD activity only in the absence of NPTs. The NTP effect is reversible and labile, and the binding protein is separable from the PLD activity by heparin-agarose chromatography. We identified this protein as the actin- binding protein gelsolin by amino acid sequencing following peptide mapping. This finding was verified by the co-immunoprecipitation of gelsolin and PLD activity as well as by the reconstitution of gelsolin- dependent nucleotide sensitive PLD activity by the addition of purified gelsolin-free PLD. Our data indicate that actin rearrangements and PLD signaling are coordinately regulated through the physical association between PLD and gelsolin and that this interaction may also serve to amplify both PLD signaling and actin reorganization.
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Affiliation(s)
- P M Steed
- Research Department, CIBA Pharmaceutical, Summit, New Jersey 07901, USA. PMS%
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